1. Field of the Invention
The present invention relates to a printing system, an image forming apparatus, an image forming method, and a non-transitory computer-readable recording medium encoded with an image forming program. More particularly, the present invention relates to a printing system which includes a print server and an image forming apparatus that performs pull printing of print data stored in the print server, the image forming apparatus, an image forming method performed in the image forming apparatus, and a non-transitory computer-readable recording medium encoded with an image forming program.
2. Description of the Related Art
A printing system is known in which when print data is transmitted from a personal computer (hereinafter, also referred to as a “PC”), an image forming apparatus represented by a multi-function peripheral is caused to print the print data at the time when a user logs in to the image forming apparatus, rather than printing the same immediately. There are two types of printing methods performed in this printing system. One involves an authenticated printing system made up of a personal computer and an image forming apparatus, and the other involves a pull printing system made up of a personal computer, an image forming apparatus, and a print server.
In the authenticated printing system, a PC transmits print data and user identification information to an image forming apparatus, and the image forming apparatus stores the print data and the user identification information temporarily. Thereafter, when the user logs in to the image forming apparatus, the image forming apparatus forms an image of the print data that is stored together with the user identification information of the logged-in user.
On the other hand, in the pull printing system, a PC transmits user identification information and print data to a print server, and the print server temporarily stores the user identification information and the print data in association with each other. Thereafter, when the user logs in to an image forming apparatus, the image forming apparatus transmits to the print server a transmission request including the user identification information of the logged-in user. When the print server receives the transmission request from the image forming apparatus, the print server extracts, from the temporarily stored print data, the print data associated with the same user identification information as that included in the transmission request, and returns the extracted print data as well as the user identification information to the image forming apparatus. When the image forming apparatus receives the print data and the user identification information from the print server, the image forming apparatus forms an image of the print data.
In the authenticated printing system, after a user is authenticated, the print data that is temporarily stored at the time of the authentication is printed. In the pull printing system, after a user is authenticated, a transmission request is transmitted to a print server. Therefore, in order to make a single image forming apparatus correspond to both of the authenticated printing system and the pull printing system, it is necessary to authenticate a user for each of the systems. Specifically, when an image forming apparatus which corresponds to the authenticated printing system receives print data and user identification information from the outside, the image forming apparatus stores them temporarily. If this image forming apparatus is applied to the pull printing system, the image forming apparatus will temporarily store the print data and the user identification information that are received from the print server after the transmission request is transmitted to the print server following the authentication of the user. Then, in order for this temporarily stored print data to be printed, the user authentication needs to be performed again.